1. Field of the Invention
The present invention relates to compositions for artificial marbles and a process for producing artificial marbles from said compositions. More particularly, this invention relates to compositions which can provide artificial marbles having superior mechanical properties and external appearances, and to a process for producing artificial marbles from the compositions by cast polymerization.
2. Description of the Prior Art
Conventionally, various kinds of the so-called artificial marble have been developed, in which methyl methacrylate (MMA) is blended with an inorganic filler comprising various inorganic substances such as aluminum hydroxide, alumina, calcium carbonate, etc. for the purpose of providing the artificial marble primarily with design effects, flame retardancy and rigidity. (See U.S. Pat. Nos. 3,775,364 and 3,847,865.)
In these conventional types of artificial marble, internal affinities such as miscibility, adhesion, etc. are poor due to substantial differences in properties between the inorganic filler and organic resin, so that the conventionally used inorganic filler has often exhibited no sufficient improving effect in relation to the mechanical properties of the artificial marble, particularly its bending strength and impact strength. In order to improve the foregoing shortcomings resulting from the use of the conventional types of inorganic filler, an artificial marble has been proposed, which is produced by surface-treating the inorganic filler with, for exmple, a silane coupling agent and then incorporating it in, for example, MMA resin, but no adequate improvement has recessarily been accomplished as yet. (See J. G. Marsuen, Appl. Polym. Symposia 14, pp. 108-109 (1970). UCC Technical Bulletin, F-43598A.)